• anticancer
• AS101
• immunomodulators
• inorganic drugs
• metalloids
• tellurium

Essential metals are fundamental for the biological functions and their dyshomeostasis can lead to pathological conditions. However, beyond essential metals, the exogenous ones can be exploited for the preparation of drugs. In this context, inorganic chemistry holds a central role in the management of several diseases. For instance, various inorganic drugs are approved for cancer treatment while other transition metals are used for different therapeutic indications. Beyond metallodrugs, even semimetals i.e., the elements which lie on the diagonal from boron to polonium, are being used in medicine where some compounds with therapeutic properties have been approved by the Food and drugs Administration (FDA) and the European Medicinal Agency (EMA). Ammonium trichloro (dioxoethylene-O,O') tellurate (AS101) is a potent immunomodulator prodrug that in the last years entered various clinical trials and was tested for a variety of potential therapeutic applications. AS101 undergoes rapid activation in aqueous milieu, producing TeOCl3− which likely represents the pharmacologically active species. Here we report on the synthesis and study of the activation process of AS101 and of two its halido-replaced analogues. Additionally, preliminary cell experiments in human retinal pigment epithelial (ARPE-19) cells have been performed to comparatively assess differences and analogies of these promising immunomodulatory agents.